Hans kruis and rudolf ga-llee



No. s2|,2571 Patented Mar. I4, I899.

' H. KRUIS & n. GALLEE.

CLAMP.

(Application filed Apr. 16, 1898.)

(No Model.)

mvENTo R6 mus Kama m RUDOLFGHLLE'E WITN 5595s; M/M few/ y THEIR ATTORNEYS.

HANS KRUIS'AND RUADOLF eA-LLEE, or VIENNA, AUS'IRIA-HUNGARY.

.CLAM P.

SPECIFICATION forming part of Letters Patent No. 621,257, dated March 14, 1899. Application filed April 16,1598. Serial No. 677,830. (No model.)

To all LU/2,0777, it may concern:

Be it known that we, HANS KRUIS and 'RUDOLF GALLEE, subjects of the Emperor of Austria-Hungary, and residents of Vienna,

in the Empire of Austria-Hungary, have invented certain new anduseful Improvements in Clamps, of which the following isa specification.

The object of this invention is to provide a metal clamp which will insure a firm and tight joint in box-corners and other like joints pf wood, board, leather, cardboard, and the ike.

In the accompanying drawings, Figure 1 is a sectional view illustrating a common form of box-clamp. Fig. 2 is a face view ofa clamp-plateembodyin-g ourinvent'ion. Figs. 3 and 4 are sectional views thereof'at right angles to each other. Fig. 5 is a view showing how our improved clamp is applied to a box-corner. Figs. 6,7, and S are views of modified forms of clamp-plates.

In using met-a1 clamps for connecting pieces of wood, leather, pasteboard, and the like for making boxes and the like the joint is produced by points cut in and'bent out of the edge or of the mass of the sheet-metal strips from which such clamps are made, the bases of such points being parallel to the longitudinal axis of the clampthat is to say, to the line on which the clamp is bentin making an edge joint. This arrangement of the points renders these clamps unsuited for connecting heavier pasteboard plates and still more unsuited for connecting wooden boards, as in the manufacture ofboxes, for which latter purpose this mode of connection would be particularly desirable on account of its simplicity, cheapness, and strength. If an edge joint has to be made by means of a metal clamp, then under the most favorable conditions the clamp-band may be applied to one of the surfaces to be connected, whereupon the points on one side of the clamp-band are driven into this surface. Afterward the clamp-band has tobe bent along its longitudinal axis or line of bending in order to drive the points on the other side of the band into the other of the two surfacesto be connected, as shown in Fig. 1. The points meet such other surface at an oblique angle and are liable to be bent and distorted, as the the grain of the material of both surfaces is parallel to the edge in which both surfaces meet, because if the direction of the fibers is at right or oblique angles to such edge the points mustbe stiff enough to cut through the fibers transversely to the grain in being driven in without being bent. This, however, would require an utterly impracticable thickness of the sheet metal from which the clamp* band is made. I

! Now in the manufacture of wooden boxes it is absolutely impossible to always make the grain parallel to the edge at which any two surfaces meet. This condition is, on the contrary, fulfilled only for two edges outof eight in the ordinary wood boxes without cover. This latter difliculty has already been appre= ciated, and it has been proposed for the purpose of removing it to twist the points after stamping and bending them outof the plane of the strip, as shown in the British Patent No. 17,763, A. D. 1895. Obviouslyin this way satisfactory results could not be obtained because the stidness of the points is materially impaired,so as to seriously interfere with dri ving them in properly. Further, the points are curved thereby, which makes it impossible to obtain a tight joint by the same, and, finally, the manufacture of these clam p-bands is by far too expensive.

According to the present invention all these difficulties are removed in the simplest and most economical manner.

The points in a clamp-band are obtained according to this invention by producing in a sheet-metal strip A two cuts 1 2, inclined to each other at a suitable angl'eand starting from one point, Fig. 2, the other ends of such cuts terminating on a straightline 3 3 at right angles to the longitudinal axis or bending-line C C of the sheet-metal strip. The tongues thus formed are then bent on the line 3 3thebase-so as to project at right angles from the plane of the strip A, Figs. 3 and 4.

Fig. 5 illustrates the modes of application of this clamp-band to an edge of a box or the like for making a joint. The clamp-band is placed with the bending-line C 0 onto the corner edge of the box, as shown in dotted lines in Fig. 5, and is then bent on this line, so that the points B enter into the surfaces to be connected, which in the case illustrated consist of wood. Now although the side edges of the points on their meetingthe surfaces are inclined to the same at an oblique angle,

yet an objectionable bending of the same cannot take place because owing to their shape the points offer a very great resistance to their being bent on a line at right angles to the line 33-their base-while neither the firmness ofthe joint nor its tightness is appreciably impaired if the points are bent on a line parallel to their base. points is preferably such that their ends slightly project from the inner side of the surfaces to be connected and are upset there. In order to increase the resistance of the points to their being bent on an axis at right angles to their base and to secure a perfectly tight joint, the outer side edge. 2 of the points B is preferably curved on the arc of a cir-' ele the center of which is at the point of intersection of the base 3 3 of the point with the bending-line C C of the strip, as shown in Figs. 2, 4, and 5. On driving in points of this form the outer side edge 2 thereof has not to displaceanymaterial in the surface to be connected, as all points of thesaid edge move along one and the same are of a circle, and, further, the points of this form perfectly fillout the space from which they have displaced any material of the surfaces to be connected on being driven in. Therefore no leak age whatever can occur. Such points the bases of which are at right angles to the bending-line may be provided on both sides of the clamp-band, as shown in Figs. 2 to 5; .but with materials having a difinite grain it may happen that in one of the surfaces to be connected the grain is at right angles to the line The length of the.

on which such surfaces meet and in the other surface parallel thereto. The points for the latter surface then cannot be provided with bases at right angles to the bending-line O C, but must have bases parallel to such bendingline, as shown in Fig. 6. The points at the other side of the clamp-band are arranged as shown in Figs. 2 to 5.

Instead of single points groups of such points may be used, as shown in Figs.,7 and 8, the arrangement being such that thetongues from which such points are formed have their sharp ends directed toward each other before being bent up. 1

For materials Without definite grain this ,arrangement of points is preferably combined with points arranged as usual-that is'to say, with points having their bases parallel to the bending-line, as shown in Fig. 8s0 that the bases of the points are on the sides of a square two of which are parallel to and two of which are at right angles to the bending-line.- By this arrangement of points an extremelyfirm connection isobtained.

We claim as our invention 1. A metal clamp for connecting edges of pieces of wood, leathenpasteboard and the like, by means of points provided on and bent 'out from such clamp, the characteristic feature of such clamp being that on at least'one side of the bending-line C O the bases of all the points are at right angles to the bendingline, suchpoints being cut and bent out from .the mass of the band. I

2. In a metal clamp having points out out of and bent up from the metal lines at right angles to the. bending-line 0f the clamp, the outer edges 2 of the points being curved on the are of a circle, as and for the purpose described.

In testimony whereof we have signed our 90 names to this specificationin the presence of two subscribing witnesses.

HANS KRUIS. RUDoLF- GALLEE.

W itn esses:

HENRY C. CARPENTER, CHAS. E. CARPENTER. 

